This worked for me. Let me know if this works for you as well? Close Plex Desktop before running this. Forcing opengl here
This is for Flatpak.
sudo flatpak override tv.plex.PlexDesktop --env=QT_QUICK_BACKEND=opengl
If using SNAP, then maybe try this.
snap list
sudo snap set <snap-name> env.QT_QUICK_BACKEND=opengl
Replace <snap-name> with the actual name of the Snap package (e.g., plex-desktop if that’s the Snap name).
snap restart <snap-name>
See if this works for you. For me, the white boxes that randomly appear are not showing any more.
